Bell-hoisting gear, a screw-cutting bench and a fortified gate
A screw and counterweight to raise a bell, a screw-making bench, a water pump and a gate with portcullis
A sheet of lifting and workshop mechanisms. In the upper corner a screw device draws a bell to its place, and a study of bells and bell-towers explains a counterweight system: a box of stones or sand ten pounds heavier than the bell descends — restrained by a small cord — so the bell rises slowly and safely while the operator holds only that ten-pound difference. At the centre stands a bench for cutting screws whose wheels a f can be changed at will, and above it a pump for water. The left margin sketches a fortified gate labelled with its bridge, machicolation and portcullis.
On this page
Screw device to move a bell
In the upper-left corner a mechanism uses a screw to draw the bell into its place.
Counterweight system for raising a bell
A box of stones or sand ten pounds heavier than the bell descends; held back by a small cord so it does not fall violently, it makes the bell rise slowly and safely, so the operator has only those ten pounds to hold even though the box weighs more than the bell.
Bench for cutting screws
At the centre a bench for making screws is drawn with the note that the wheels a f be arranged so they can be changed at will.
Water pump
Above the screw bench a device is labelled simply as a pump for water.
Fortified gate with drawbridge and portcullis
A figure on the left margin lays out a defended gateway, its parts labelled in sequence: bridge, gate, machicolation (dropping-hole), gate, portcullis, gate.
Bells and bell-towers (campanili)
The counterweight note accompanies drawings of bells and bell-towers (campanili), sketched at the right and upper right of the sheet, for which the hoisting mechanisms are designed.